Process for preparing twistless yarns



.- 1 f l. ELDBQLINGER Pnocm'ss FORPREPARING TWIS'I'LESSYARINS Original Filed Jan. 9,1965

QE/8 L x? INVENTOR. EDGAR DARE BOLINGER BY ATTORNEY United States Patent ABSTRACT OF THE DISCLOSURE 'A process for preparing twistless yarn comprising sizing a roving prepared according to' the woolen process With a'composition' containing an adhesive agent such as gelatin, an insolubilizing agent such as formaldehyde, and optionn fgc i i ent such ja -f oHoidal silica. and t re;

after compacting said roving while simultaneously drying the. sized roving. Yarns prepared in this manner, though twistless-, have sufficient strength to be used in preparmg commercial fabrics. l

This application is a continuation of application Ser. No. 250,320, filed Jan. 9,, 1963, now abandoned. This invention relates to a process for the preparation ofJtwistless. yarnfand, more. specifically -to. a. method for the preparation of twistless yarn from fibers having interlocking characteristics an d'to fabrics produced from suchyarns. d a t t .i Because'of the"greatexpense involved in each turn of twistimpa'rted to a yarn, effor'ts'fhave been made to prepareyarns with reduced twist or preferably zero twist. Zero twist yarns produced from broken bundles of synthetic continuous filamentshave beenidisclos ed in.U.S. an-set. No. 2,946,181. Zero twist yarns produced from synthetic and naturally; occurring vegetable staple fibers havebe'e'n'disclose'd in I JYS. Pat; Ser. No. 2,689,813. Zero. twistorjt'wistle'ss yarn such as'disclosed in the aforementlbnedjp'atents is, however, lackin-gin strength. Lackof, strength in the brokenbundleslof twistless synthetic mono filaments and in synthetic and naturallyoccurring vege table's'ta'ple fibers is due in part to the nature of the fibers; While producing a crimp in a fiber will promote interfiber cohesion, fibers havingno surface characteristics in and of themselves which will promote an interlocking action have, in the absence of twist, little strength.

one; class of naturally occurring fiber and more specifically the ,class. consisting. of-wool and wool-like fibers ha" ain surface characteristics which promote int er-. fiber bonding even} in the absence of twisting, Wool and We l-like fibers which include'rabbit -fur,.;llama,1camel. hair, mohair, alpaca, Vicunaand guanaco have outside, surfaces made up of flat irregular horny cells .or scales.v The ,-scales overlap, not unlike the shingles of a roof with the free (end projecting. outward and pointed ;toward the tipfofj the' hair When I one wool ;or wool;like;; fiber is moved against anothen a frictionais set-,up. As might beexpeaed from the existence and orientation-of the scales; this friction i's.. directional, being greatest .when the fibers w are being moved with the tip end leading. The ability of woolor. wool-like fibers .to interlock is;known the directional friction effect. l y

In additi n to the ability of. wool orwool-like fibers to interlock, itshould be noted that, Wool --or wool-like textilefmaterials have great value,for' their ornamental propertiesand are often-useful in fields where exceedingly high:- strength is not a prerequisite to their usage. Woven felt for instance, because ofiits fine finish, uniform thickness and frictional qualities finds application-as coverings for tennis balls, filtering cloths, andrcushioning elements 6 for devices such as pianos and typewriters. Woolen fabrics with soft hand and high nap are also desirable for the manufacture of two ply fabric of the type used in the manufacture of sports clothing. The two ply fabrics of this type may have both plies of fabric material or may have one woolen ply backed with a ply consisting of a polymeric resin sheet material.

It is therefore an object of this invention to provide a method for the preparation of a twistless yarn, from fibers having interlocking characteristics, which has suflicient strength to produce a commercial fabric.

It is another object of this invention to provide a method for the preparation of a sized twistless woolen yarn which has suflicient strength to produce a commercial fabric.

It is still another object of this invention to prepare a fabric from a twistless woolen yarn and subject the fabric to a post weaving operation which will result in a greatly strengthened product.

In the drawing, the figure is a diagrammatic illustration of an'appa'ratus suitable for processing the invention.

'In accordance with this invention it has now been discovered that it is possible to impart unexpected amounts of strength to a twistless yarn containing at least some fibers having the ability to interlock by sizing the yarn with a sizing composition containing an adhesive agent and preferably a sizing composition comprising an adhesive agent and a frictioning agent. It should be understood that while some wool or wool-like fibers having the ability to interlock must be present, that blends of synthetic and vegetable fibers with the wool or wool-like fibers are also within the scope of this invention.

Where an exceptionally soft fabric is desired, the sizing composition employed should be a water-soluble sizing composition. The water-soluble sizing composition will provide the strength necessary to weave the twistless yarn, but will be easily removable by washing operations once the fabric is formed. The fabric which is free of sizing composition will therefore be a fuller and softer fabric. Where, however, fabric strength is of greater importance than softness and fullness, a Water-insoluble sizing composition or a composition which is capable of being insolubilized should be employed.

The frictioning agent is preferably a frictioning agent of the colloidal silica type. The adhesive agent may be an adhesive agent such as, for instance, gelatin, egg albumin, polyvinyl alcohol-polyvinyl acetate copolymer. In addition to the frictioning agent and adhesive agent components of the sizing composition, the sizing composition may contain insolubilizing agents for fixing larger amounts of sizing compound in the finished product. Without the presence of an insolubilizing agent, substantially all of the sizing composition is removed from the fabric in finishing operations. The insolubilizing'agent may be an agent, such as, for instance formaldehyde or a formaldehyde donor such as MeOMe Hydantoin.

The following specific examples of sizing compositions are given for purposes of illustration and should not be considered as limiting the spirit or scope of this inven-- tion. Theindividual components of the various sizing compositions are given in percent by weight.

EXAMPLE I Removable sizing composition Percent Gelatin 12.0 Glycerol 1.9

polyoxyethylene glycol groups marketed by Syton DS (colloidal dispersion of 30% Si in water marketed by Monsanto Chemical Co.) 1.3 Surfonic N-95 (nonyl phenyl polyoxyethylene glycol ether having 9.5 ethoxide groups marketed by Jefferson Chemical Co.) 0.1 Water 84.8

EXAMPLE III Removable sizing composition Percent Egg albumin 12.0 Cellulose methyl ether (0.5% water solution having a viscosity of 400 cps.) 1.8 Syton DS (colloidal dispersion of 30% Si0 in water marketed by Monsanto Chemical Co.) 1.3 Surfonic N-95 (nonyl phenyl polyoxyethylene glycol ether having 9.5 ethoxide groups marketed by Jefferson Chemical Co.) 0.1 Water 84.8

EXAMPLE IV Permanent sizing composition Percent Elvanol 51-05 (polyvinyl alcohol-polyvinyl acetate copolymer marketed by E. I. du Pont de Nemours & Co.) 12.0 MeOMe hydantoin 1.8 Syton DS (colloidal dispersion of 30% SiO in water marketed by Monsanto Chemical Co.) 1.3 Surfonic N 95 (nonyl phenyl polyoxyethylene glycol ether having 9.5 ethoxide groups marketed by Jeflferson Chemical Co.) 0.1 Water 84.8

EXAMPLE V Permanent sizing composition Percent Gelatin 12.0 Glycerol 0.75 MeOMe hydantoin 0.15 Syton DS (colloidal dispersion of 30% SiO in water marketed by Monsanto Chemical Co.) 3.3 Water 83.8

The sizing compositions are applied by contacting a running length of sliver or roving with a sizing composition and then passing the sized roving into a heated chimney where the roving is dried simultaneously to being compacted by means of a false twisting operation carried out within the heated chimney. It should be understood that the compacting operation need not be a false twisting operation but maybe a compacting operation produced by other means such as, for instance, by passing the sized-roving into a reciprocating pair of rollers or a reciprocating'pair of a'pron webs.'It should also be understood that the rovings' employed are rovings prepared according to the woolen process, that is to say, the rovings in contradistinction to rovings prepared according'to the worsted process have fibers which are thoroughly intermingled without regard to direction.

An evaluation of the twistless yarns of this invention was made by comparing sized twistless yarns and more specifically yarns sized with the sizing composition of Example V with a twistless wool yarn which is free of size, the data from the 'comparison being set forth in the table designated as Table I. The comparisons were based on determinations of elongation and breaking strength. Elongation may be defined as deformation caused by a tensile force expressed in terms of the original length. Breaking strength may be defined as the ability of yarns 4 to resist rupture by means of tension. The breaking strength is determined by placing a single strand of each yarn being tested into the jaws of an Instron machine. The Instron machine, which is a constant-rate-of-traverse machine, applies an increasing load to the test strand until the breakage pointis reached. The average single strand breaking load is an arithmetic mean of a plurality of breaking tests. i 1

The breaking elongation of the test strand isdetermined. by measuring the specimen at zero-load and at break 7 and by applying the following formula:

' IABi E Break Sizing liar; =Percenti composition .AYg-g- Unsizedfruut- Example V.

. As can be-seenirom :the; data: ofiaTablevLthesized twistless wool yarn of'this invention-haszvastlyiincreased break strengthwand-zimproved elongation resistanceiovcr unsized twistless 1WO 01 ;yaIl1;:-.",I'h6 improvements :obtained bysizing enable the twistless Woolf-yarn tobeemployediinweaving: --or knitting -..operati0n s,:,1lthe'eknitting ;;1operations: being the preferred usage.

After weaving the twistlesswooliyar-n of this invention intoa fabric, the fabric is preferably subjected to a fulling operation, The ful ling dperatio 1r'1vo tion andheat and isessentr l vlthe a diw dth' 9 t r wherebyithe inter fiber bondingof'the fibers locking characteristiqs i'sincreased; run r i ui h vefi imi I m o f a stoclcor harnrn]rjifllnig rnill,' or by,me s ora ota fif l n mi io o li g h f -s m s i ies t "tho elrfep ra sr et n t common to fulling operations such as tackifig'andsbapirigl A better understanding of the invention' may -'b'e'" [iad from a discussion of the'drawings. In the drawing, a roving lis' passed ove'r guide roll- 5 undei' immersion rbll 3 througlr sizing b-ath 2 and thn' into (the nip of a pair-"bf idler rolls '43 The sized roving 1 is then pas'sed around; guide roll 5 =into chimney 6 whiclr is heated-by assing hbt air intochimney fi thro'ugha=pipe' 12; The sized rovin'g' is passed throughi a false" 'twistin' device" 7 wherehy th'e roving 'i's compacte'd 'through a -length ext'e'nding trom the nip of idlerrolls 4 to the fp'i'n nlember 8 =of =fa lsetwist i'ng' deVice' 7-.' The" compacted yarn is theh -passed bver 'guide rolls '5 a pluralit-y ofti'fiies in- 'order to' conrplete v the drying of the sized compacted yarn andithe'hi passed fibers of the filling yarns with the fibers of the warp yarns.

The finished fabric has a pleasing appearance and a soft hand and is especially suitable for use in conjunction with a polyurethane foam sheet. By laminating the fabric of this invention to a polyurethane foam sheet, a product is produced which has high strength and pleasing hand and appearance. While foam backed fabrics are commonly referred to as laminated fabrics, that is, fabrics secured to a preformed sheet of foam material, the foam portion may also be applied by coating the fabric with a foamable composition and then foaming the composition in place.

That which is claimed is:

1. A process for the preparation of a twistless yarn comprising preparing a roving according to the woolen process, sizing the roving having some fibers with interlocking characteristics with a sizing composition comprising an adhesive agent and an insolubilizing agent, and then compacting by false twisting the sized roving simultaneous to drying the sized roving.

2. The process of claim 1 wherein said sizing composition further comprises a frictioning agent.

3. The process of claim 1 wherein said fibers having interlocking characteristics are wool fibers.

4. A process for the formation of a twistless yarn fabric comprising preparing a roving according to the woolen process, sizing the roving having some fibers with interlocking characteristics with a sizing composition comprising a frictioning agent, an insolubilizing agent and 6 an adhesive agent, compacting by false twisting said roving simultaneous to drying said roving, and then weaving said roving.

5. The process of claim 4 wherein a fulling operation is carried out subsequent to said weaving operation.

References Cited UNITED STATES PATENTS 2,454,830 11/1948 Newton 57-164 X 2,521,055 9/1950 Foster 28-75 X 2,527,329 10/1950 Powers et al. 2,638,734 5/1953 Cruz 57164 2,743,194 4/1956 Berner et a1 28-75 X 2,834,704 5/1958 Lawrence 156-180 2,946,180 7/ 1960 Tissot et a1. 57156 3,068,151 12/1962 Haefele 117--141 X 3,099,907 8/1963 Masurel et a1 57--156 3,151,439 10/1964 Dusenbury 57164 3,167,468 1/ 1965 Lovelace et a1 28-75 X OTHER REFERENCES German application (Althof) 1,112,928 August 1961, 57-156.

JAMES KEE CHI, Primary Examiner US. Cl. X.R. 

